Blade ring saw blade

ABSTRACT

A flat-sided annular blade for a blade ring saw for cutting hard materials such as tile along straight paths and curved paths in which the workpiece is moved through the central portion of the blade. In addition to the usual sintered abrasive diamond coating on the outer peripheral portion of the blade, the inner peripheral portion preferably is tapered to a curved inner edge and also is coated with an abrasive, preferably an electroplated diamond coating providing smoother sawing operation and a finishing action on the workpiece.

REFERENCE TO PRIOR PROVISIONAL APPLICATION

This application claims the benefit of prior copending provisionalapplication No. 60/442,391, filed Jan. 24, 2003.

BACKGROUND OF THE INVENTION

This invention relates to abrasive saw blades of the type having anarrow, substantially flat-sided annular body typically composed ofmetal, an open central portion for movement of the workpiece through theblade, and an outer peripheral surface coated with an abrasive. Thetypical abrasive is a coating of powdered diamond particles applied in asintering process and covering not only the outer periphery but also aportion of each flat side of the blade along the periphery. A sawassembly using blades of this type is shown in my U.S. Pat. No.6,632,126 B1 (“the '126 patent”) issued Oct. 14, 2003 and entitled BLADERING SAW ASSEMBLY.

Saws of the type shown in the above-identified patent support thering-shaped blade around its inner and outer peripheries and rotate theblade at high speed to cut a workpiece with the abrasive-coated outerperiphery. Because the blade is narrow and the interior of the blade isopen, the workpiece can be turned during the cutting operation and movedwithin the blade to permit the blade to cut along irregular, curvingpaths. A typical use of such a blade is for cutting very hard materialssuch as tile. The flat-sided ring has sufficient strength to be driventhrough the tiles at substantial cutting rates. Details of constructionand operation of such a saw assembly are shown and described in theabove-identified patent, and have been made public through theadvertising and sale of such saw assemblies by Gemini Saw Company ofTorrance, Calif., under the trademark “Revolution.”

An earlier, lighter duty saw shown in U.S. Pat. No. 4,576,139, entitled“Rigid Wire Saw Wheel Apparatus For Very Hard Materials,” (“the '139patent”) uses a diamond-coated wire ring that is supported and driven ina generally similar manner. This saw is designed for sawing glass andceramics, but is not well-suited for heavy duty cutting because oflimited cutting speed. With the flat-sided ring blade of the '126patent, much greater cutting pressure can be applied and curved cuts canbe made, although not as sharply curved as with a wire blade.

SUMMARY OF THE INVENTION

This invention resides in an improved flat-sided blade for blade ringsaws in which the inner periphery of the ring and at least a portion ofeach flat side along the inner periphery also are covered with anabrasive coating, which protects the inner peripheral portion of theblade ring body from wear through contact with workpieces and, at thesame time, utilizes the inner portion of the body as a grinder duringthe cutting of curves. This provides a smoother cutting action, a betterfinish on the workpiece, and the capability to cut much tighter curves.In essence, the trailing portion grinds in the opposite lateraldirection from the leading portion during turning, thereby creatingadditional clearance for turning. Also, it is possible with such a bladeto cut backwards, using the inner periphery as the leading edge.

The preferred embodiment of the invention has a sintered diamond coatingon the outer peripheral portion, as shown in the '126 patent, coveringpart of each flat side along the outer periphery, and an electroplateddiamond abrasive coating covering the inner periphery and the remainderof the unsintered body of the blade. The sintered coating is believed toprovide a thicker coating with greater abrading capacity to perform theprimary cutting function of the blade, and electroplating typicallyprovides a thinner abrasive coating which does not wear away as quicklyand therefore effectively protects the metal body while providing theedge-finishing function. Other coatings and coating patterns may beused, however, and the particular coating and patterns that are shownand described are not to be regarded as limitations.

An important advantage of this invention is substantially increased lifeof the saw blade. This is attributed to the protection of the body fromdamage, and the contribution of the trailing inner portion to thecutting capability after the leading outer cutting portion wears down.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a blade ring saw blade embodyingthe novel features of the present invention;

FIG. 2 is an enlarged fragmentary elevational view of a portion of theouter peripheral edge of the blade shown in FIG. 1; and

FIG. 3 is a greatly enlarged fragmentary cross-sectional view takenalong 3-3 of FIG. 1, not exactly to scale, with diamond particlesindicated diagrammatically on the inner peripheral portion, of theblade.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in the drawings for purposes of illustration, the presentlypreferred embodiment of a saw blade 10 for a blade ring saw assembly isan improvement on the basic saw blade shown in the '126 patent and soldby Gemini Saw Company as part of the “Revolution” saw, Reference is madeto that patent for details of a representative saw assembly for use witha blade in accordance with the present invention. It will be evidentthat a blade of this type also may be used in a saw assembly of thegeneral type shown in the '139 patent, with modifications.

As shown in the drawings, the blade 10 has a ring-shaped or annular bodyor core 11 (FIG. 3) of suitable tool metal, preferably a carbon steelalloy. The blade has substantially flat sides 12 between circular outerand inner peripheral edges 13 and 14, respectively, the inner peripheraledge defining a large open central portion of the blade.

The outer peripheral edge of the blade 10 is formed by an abrasivecoating 15 on the body 11, preferably a sintered powered diamond coatingthat extends partially over each side of the body. A short radial widthof the outer portion 16 of the body preferably is of reduced thicknesswithin the sintered coating, as shown in FIG. 3, to receive asubstantially greater thickness of wearable coating 15. The portion 16of the body that is reduced thickness is a rib that is thin enough to beworn away with the diamond coating in service use without interferingwith the normal cutting action of the blade.

In accordance with the present invention, at least the side walls of thebody 11, and preferably the entire inner periphery of the body 11, arecovered with an abrasive coating 17 that protects the body againstexcessive wear and smooths the contact of the blade 10 with workpiece,both for a finer finish on the workpiece and for smoother operation andbetter wear of the saw blade. While this coating may take various forms,including a full sintered coating for the blade (not shown), thepreferred coating is an electroplated diamond coating, shown as coveringthe remainder of the body of the blade that is not covered by thesintered coating 15 on the outer peripheral portion 16. For functionalpurposes, the most important portion of the additional coating 17 isalong both sidewalls close to the inner periphery, and secondarily onthe inner edge 14 itself. It is convenient and preferred, however,simply to electroplate all of the body 11 that is not covered by thesintered layer, as shown.

As shown in FIGS. 2 and 3, the inner peripheral edge 14 of the blade 10may be rounded, as indicated, to modify and soften the grinding andfinishing action of the inner portion during turning of a workpiecerelative to the blade. The presently preferred configuration of the body11 of the blade 10, from the thicker outer diamond layer 15 to the inneredge, begins with substantially flat side surfaces 20 extending abouthalfway from the outer diamond layer 15 to the inner edge 21 of thebody, and then tapering gradually at 22 toward the inner edge, at asmall angle with the flat sides 20, such as between ten and twentydegrees. The inner edge 21 is rounded so that the inner edge 14 formedby the diamond coating on this edge will be similarly rounded.

Blades for this type of saw assembly can be made in various sizesaccording to the parameters set forth in the '126 patent. As an exampleof a representative blade, not to be considered specific limitations,the blade 10 can have an outside diameter of approximately ten inches,an inside diameter of approximately nine and one-quarter inches, a metalbody 11 or core approximately 0.042 to 0.052 of an inch thick, reducedto approximately 0.01 inches thick in the portion 16 inside the sintereddiamond layer 15. This layer may have a total thickness of approximately0.55-0.65 of an inch and forms about one-half the radial width of theblade 10. The electroplated coating 17 covers the remainder of the body11, to a thickness that preferably is not greater than the thickness ofthe sintered portion 15 on each side of the body, and may be slightlythinner so as to follow closely within the space, or “kerf” (not shown),cut in a workpiece during a straight cut, to avoid unnecessaryenlargement of the kerf. The rounded inner edge 21 may be sized andshaped to produce an inner radius for the electroplated diamond coatingon the order of 0.330 to 0.340 of an inch, the entire coating beingapproximately 0.010 to 0.015 of an inch thick.

Upon turning of the workpiece relative to the blade 10 to make a curvedcut, the trailing inner edge 14 and the inner peripheral portion willswing out, relative to the direction of curvature, as the opposite sideof the leading edge portion swings in, thereby moving into engagementwith the curved side edge of the workpiece that has been formed by thecutting action of the leading edge of the blade. Because of the slighttaper of the inner edge portion 22 of the body 11 and the correspondingtaper of the inner diamond layer 17, this swinging action on both sidesof the inner edge will, in effect, slightly delay the contact of theinner diamond coating, at the inner edge, with the edge surface of thesaw kerf, and thus will avoid harsh or excessive cutting engagement atthe inner edge. This occurs in both directions of curvature, andproduces a smoother cutting action of the blade 10 as well as a finefinishing or smoothing operation on the sidewalls of the workpiece.

Further, providing an abrasive coating on the inner peripheral edge 14of the blade 10 provides the blade with the ability to cut reversely aswell, during which the outer coating serves the smoothing and finishingfunction performed by the inner coating 17 during forward operation.This is a bonus value of the blade, which is designed for one-directioncutting movement as its primary function but sometimes can be operatedto advantage in reverse.

It bears emphasis that the invention is an improvement in a flat-sidedring blade of the type disclosed in the '126 patent, in which the outerperipheral portion of the blade is coated with an abrasive coating toform an outer cutting element and the inner edge surface of the ring wasbare metal. This had a tendency to cause blade wobble upon contact witha workpiece in the later stages of the life of a blade. Covering theexposed inner portion of the blade with abrasive cutting material notonly provides a finishing action but also reduces blade wobble andmaintains stability, and produces a substantial increase in the usablelife of the blade.

Also to be noted is the fact that different abrasive coatings may beused on different portions of the blade 10, with similar but somewhatvarying results. Sintered diamond particles buried in powdered metalprovide more effective cutting action than electroplated diamondparticles, which typically provide a thinner layer. While anelectroplated diamond coating could be used on the entire body, thepreferred combination shown herein is believed to provide for optimumresults—greater cutting capacity for the outer, primary cutting elementand a durable abrasive coating for the inner, secondary cutting element.

A variety of different dimensions can be provided for a saw blade ofthis type, and a variety of abrasive coatings may be provided, allwithin the knowledge of those who are skilled in this art. Thisdescription is of a representative embodiment of the invention. Othermodifications within the spirit and scope of the invention will beapparent to those skilled in the art.

1-7. (canceled)
 8. A blade ring saw blade for making straight and curvedcuts in hard workpieces, having, in combination: an annular body havingan outer peripheral edge, an inner peripheral edge defining a largecentral opening for relative movement of the workpieces through theblade during making of curved cuts, and substantially flat sides thatare substantially wider than the thickness of said edges, the largecentral opening defining a radius that is greater than the annular widthof the blade between the inner and outer peripheral edges; an abrasivecoating on said body defining said outer peripheral edge andsubstantially flat outer portions of sidewalls of the blade adjacentsaid outer peripheral edge; and an abrasive coating on said bodydefining said inner peripheral edge and substantially flat innerportions of sidewalls of the blade.
 9. A blade ring saw blade as definedin claim 8 wherein at least a portion of said abrasive coating comprisesa sintered diamond particle coating.
 10. A blade ring saw blade asdefined in claim 8 wherein at least a portion of said second abrasivecoating comprises an electroplated diamond particle coating.
 11. A bladering saw blade as defined in claim 8 wherein said sidewalls aresubstantially parallel adjacent said outer peripheral edge and taperinwardly adjacent said inner peripheral edge.
 12. A blade ring saw bladeas defined in claim 11 wherein said inner peripheral edge is rounded.13. A blade ring saw blade for making straight and curved cuts in hardworkpieces, having, in combination: an annular metal core havingsubstantially flat sides, narrow inner and outer peripheral edges and acentral opening for permitting relative movement of the workpiecesthrough the body during cutting of curves, the central opening defininga radius that is greater than the annular width of the blade between theinner and outer peripheral edges; an abrasive coating on the outerperipheral edge portion of said core for cutting in a forward direction;and an abrasive coating on the inner peripheral edge portion of saidcore for finishing the edge of the workpiece during cutting of curves.14. A blade ring saw blade as defined in claim 13 wherein at least aportion of said abrasive coating comprises a sintered diamond particlecoating.
 15. A blade ring saw blade as defined in claim 13 wherein atleast a portion of said abrasive coating comprises an electroplateddiamond particle coating.
 16. A blade ring saw blade as defined in claim13 wherein said abrasive coating is selected from the group comprisingsintered diamond particle coatings and electroplated diamond particlecoatings.
 17. A blade ring saw blade for making straight and curved cutsin hard workpieces, having, in combination: a ring-shaped body havingsubstantially flat sides and narrow inner and outer peripheral edges,and a portion of reduced thickness forming a rib extending outwardlyfrom said outer peripheral edge around the body; an abrasive coatingthicker than said body extending around said outer peripheral edge onsaid rib and forming an outer peripheral cutting element for said bladefor making the curved and straight cuts in the workpieces; and anabrasive coating covering the flat sides and inner peripheral edge ofthe body to form an inner peripheral cutting element for finishingcurved cuts in the workpieces and providing smoother action as well asfor cutting reversely; said inner peripheral edge and said abrasivecoating thereon defining an open central portion of said bladepermitting the workpieces to be turned relative to said blade to makethe curved cuts.
 18. A blade ring saw blade as defined in claim 17wherein at least a portion of said abrasive coating comprises a sintereddiamond particle coating.
 19. A blade ring saw blade as defined in claim17 wherein at least a portion of said abrasive coating comprises anelectroplated diamond particle coating.
 20. A blade ring saw blade asdefined in claim 19 wherein said inner cutting element is thinner thansaid outer cutting element.
 21. A blade ring saw blade as defined inclaim 17 wherein said abrasive coatings is selected from the groupcomprising sintered diamond particle coatings and electroplated diamondparticle coatings.
 22. A blade ring saw blade as defined in claim 17wherein said body has sides that are substantially flat adjacent saidportion of reduced thickness and then taper inwardly toward said innerperipheral edge, and has a curved inner edge.
 23. A blade ring saw bladeas defined in claim 17 wherein said blade has an outside diameter ofapproximately ten inches, an inside diameter of approximately nine andone-quarter inches, a metal body approximately 0.042 to 0.052 of an inchthick, a first cutting element approximately 0.55 to 0.65 of an inchthick, and a second cutting element having a thickness less than thethickness of the first cutting element.
 24. The blade ring saw blade ofclaim 17, wherein a first abrasive coating is provided around said outerperipheral edge and a second abrasive coating covers the flat sides andinner peripheral edge.